A top Senate Democrat says his party has been doing some contingency planning in case the Supreme Court spikes some or all of the health reform law on Thursday — even though they’ve insisted that the law will be upheld.

“We have different proposed drafts for different contingencies,” Senate HELP Committee Chairman Tom Harkin told reporters when asked about a response to the court ruling.

Harkin offered no details of how Democrats might respond under different scenarios. But he suggested it would be wise for his colleagues to react quickly, with the goal of “getting in the mix right away so that the American people know we have something that if [the justices] remove it, we could take care of whatever the Supreme Court did.”

If the court doesn’t uphold or strike down the entire law, the most likely scenarios are either a ruling that overturns the mandate by itself, or one that gets rid of the mandate and guaranteed coverage for people with pre-existing conditions.

Even if Harkin or other Senate Democrats did propose legislation to replace those pieces, the chances that it would get through the closely divided Senate — in an election year, with Republicans united against the health care law — are slim to none.

But don’t mistake Harkin’s contingency planning as resignation for a loss in the high court.

“They could uphold the whole law, which would be fine with me,” he said with a smile.